header{
    padding: 0px 16px;
    div{
        line-height: 40px;
        justify-content: space-around;
        border-bottom: 2px solid blue;
    }
}
main{
    overflow: scroll;
    padding: 0px 16px;
    .main-course-item{
        display: block;
        position: relative;
        height: 210px;
        overflow: hidden;
        .course-img{
            width: 100%;
            height: 100%;
            
        }
        .title,.desc{
            position: absolute;
            color: #fff;
        }
        .title{
            bottom: 40px;
            left: 10px;
        }
        .desc{
            bottom: 20px;
            left: 10px;
        }
    }
    .main-course{
        .main-course-item{
            height: 140px;
        }
    }
}